The invention relates to the adjustment of the angular keying or setting of coaxial elements such as for example a shaft and a steering wheel of, in particular, an automobile.
In certain applications, it is necessary to be able to choose the relative keying, in particular the angular keying, of a steering wheel on its shaft. This is the case for example in the automobile field.
As is known, steering wheels used for steering automobiles are usually fixed on the shaft of the steering column by means of splines associated with screw threads and cones. This permits transmitting, without play, the torque developed by the driver of the automobile to the road steering wheels. Some steering wheels are constructed in the form of a single-piece element and others are directly welded to the shaft.
For reasons of, in particular, appearance and comfort, it is necessary to be able to choose and fix, in particular at the moment of the construction of the vehicle, the initial relative angular keying of the steering wheel on its shaft. It may also be necessary to slightly readust this adjustment following maintenance or repair of the vehicle.
Such an angular keying essentially is for the purpose of causing the position of the road steering wheels of the vehicle corresponding to a straight-ahead travel to coincide with the symmetrical position of the branch or branches of the steering wheel relative to a plane parallel to the longitudinal median plane of the vehicle.
Indeed, it has been found that it was particularly disagreeable, and even sometimes a hindrance, for the driver when, with the road steering wheels oriented in the straight-ahead position, the steering wheel is not strictly in a comparable attitude.
As is known, such a strict keying is not easy to achieve directly on manufacturing lines or in the workshop and the techniques at present employed do not permit a convenient adjustment of this type.
Indeed, the steering wheel is usually mounted on its shaft of the steering column by means of an assembly comprising splines, usually including forty splines. This means that it is only possible to modify the relative positions of the steering wheel and shaft by a step of approximately 9.degree.. When it is desired to obtain a progressive and continuous adjustment, it is therefore necessary to avoid the restriction imposed by splines. An interposed mechanism is then necessary.
Solutions already have been proposed.
For example, French patent No. 2,557,992 proposes employing an intermediate sleeve or socket placed between the steering wheel and the column. Additional members are also employed which are relatively complicated in structure and require machining of a relatively high precision. This solution is complex owing to its structure and its kinematics. Moreover, this solution requires an additional financial outlay for the additional parts and the labour, in particular for the assembly.